An alleged prostitute charged with murdering a South Bay millionaire was one of his "main girls," had knowledge of the layout of his mansion and was being helped financially toward buying a new home, police said in court records released Monday.

Katrina Fritz, 32, of Pittsburg was receiving $3,000 a month from Raveesh "Ravi" Kumra, 66, a cell-phone entrepreneur and former owner of Mountain Winery in Saratoga, to help her on a down payment toward buying a home, Monte Sereno/Los Gatos police Detective Cpl. Erin Lunsford wrote in documents filed in Santa Clara County Superior Court.

Lunsford cited a letter found on Kumra's computer, apparently to be notarized, saying that he would be paying her up to $30,000 toward the home.

Kumra's body was found Nov. 30 after his wife summoned police to the couple's ransacked, 7,000-square-foot home in Monte Sereno, in the hills west of San Jose. Kumra died of asphyxiation after his assailants left him gagged with packaging tape as they beat his wife and told her to "be quiet if you want to live," police said. They made off with cash, jewelry and rare coins.

Fritz was charged Friday with murder and robbery, the same counts that were lodged against three other defendants including her brother, Deangelo Austin. Phone records showed numerous calls between the siblings, and placed Austin in the area of the victim's home, at the time of the slaying, police said.

Sources say Austin, 21, is affiliated with an East Oakland gang called the Money Team. Police believe members of the gang are responsible for a surge of violence in Oakland as well as home invasions of Asian and Indian families around the Bay Area.

Authorities say Kumra frequently hired prostitutes, including Fritz and another woman charged in the case, Raven Dixon. Fritz was known as one of Kumra's "main girls," another alleged prostitute told police. The prostitutes would use a side door to get into the home when his wife was gone or visit him at friends' houses or at hotels, Lunsford wrote.

Several prostitutes "would have run of the house, able to go anywhere including (Kumra's wife's) room when she was not there," a witness told police. Fritz had even visited Kumra's home with her children, police were told.

At one point, however, Fritz became angry at Kumra, accusing him of having given her a sexually transmitted disease and also because Kumra had told her "he was running out of money and would not be able to pay for any child they might have together," Lunsford wrote.